US president-elect Joe Biden has named several top advisers from his election campaign and a Democratic congressman as senior White House aides, sticking with a tight inner circle as he transitions to the White House.

Mr Biden is focused on preparing to take over the presidency on January 20, despite President Donald Trump’s efforts to reverse the outcome of the November 3 election.

Biden presidential campaign manager Jen O’Malley Dillon, the first woman to lead a winning Democratic presidential bid, will be named a deputy chief of staff, Mr Biden said in a statement released by his transition team.

Longtime close advisers Mike Donilon and Steve Ricchetti will join the White House as senior advisor to the president and counsellor to the president respectively.

Dana Remus, the campaign’s top lawyer, will be senior counsel to the president.

Another close adviser, Ron Klain, was already named chief of staff.

Joe Biden with former Ebola Response Coordinator Ron Klain in 2014. Photo: Getty

US Representative Cedric Richmond, who was a co-chair of Mr Biden’s campaign and former chair of the Congressional Black Caucus, will vacate a House seat in Louisiana to join as a senior adviser and Director of the White House Office of Public Engagement.

Mr Biden, who may name more staff soon, could still be weeks away from naming his cabinet appointees.

The former vice president is also due to discuss national security threats on Tuesday with his own team of advisers, rather than current government officials, as the Trump administration has blocked him from receiving the classified intelligence briefings normally accorded to an incoming president.

General Services Administrator Emily Murphy has not yet recognised Mr Biden as the “apparent winner,” which is needed to release government funding and office space to the president-elect.

A Murphy spokeswoman said the administrator was following precedent and would make a decision once the winner is clear.

Tweet from @Transition46

One of Mr Trump’s legal challenges will get a hearing on Tuesday in a Pennsylvania federal court, where another setback would likely doom his already slim chances.

US District Judge Matthew Brann will hear arguments in a Trump campaign lawsuit that seeks to block the state’s top election official from certifying Mr Biden as the winner.

To remain in office, Mr Trump would need to overturn results in at least three of the closely contested states in unprecedented fashion, and has no apparent legal means to do so.

Trump supporters are also clinging to hope that recounts could reverse state results, even though experts have said Mr Biden’s margins appear insurmountable.

Georgia is undertaking a manual recount on its own but in Wisconsin the Trump campaign would have to pay for a recount in advance.

The Wisconsin Elections Commission on Monday estimated such a recount would cost $US7.9 million ($A10.8 million).

Trump campaign spokeswoman Erin Perrine said the campaign would decide whether to pursue a Wisconsin recount in the next few days.

Mr Biden won Wisconsin by about 20,000 votes.

-AAP